Single-step dilatation in percutaneous nephrolithotomy, its safety and efficacy: A prospective, single-center study

A Comparison of the Alken Metallic Telescopic Dilator and Amplatz Serial Dilator for Renal Access in Percutaneous Nephrolithotomy

BACKGROUND

Access to the renal calyx is a challenging and crucial step for a successful percutaneous nephrolithotomy (PCNL). There are different methods of access tract dilatation, and there is no consensus on which method is the best. We conducted a comparative retrospective study on the safety and efficacy of the Alken metallic dilator and Amplatz dilator for renal access in PCNL.

METHODS

We retrospectively reviewed the medical records of 80 patients who underwent PCNL between March 2023 and February 2024, and they were divided into two groups. Group A (n=42) comprised patients where Alken dilators were used, while group B (n=38) comprised patients where Amplatz dilators were used. Safety parameters, that is, perioperative bleeding, blood transfusion, access time, postoperative fever, and urosepsis, were compared between the groups. Efficacy in terms of successful renal access and stone clearance was also compared.

RESULTS

The mean access time (mins) was longer in group B than group A (8.1 vs. 7.3, p=0.012). The intraoperative bleeding was more in group B (15.7% vs. 4.7%, p<0.001). Group B had more hemoglobin (g/dl) drop (1.3 vs. 0.7, p<0.001) and need for blood transfusion (18.4% vs. 7.14%, p<0.001) and VAS score (p<0.001) than group A. Postoperative urosepsis was more common in group B. Efficacy in terms of successful renal access and stone clearance was comparable.

CONCLUSION

The Alken dilator group has a lower rate of blood transfusion and postoperative VAS score. The Amplatz dilator group had more incidences of postoperative urosepsis. The efficacy in both groups was comparable.

A comparative study between one step dilatation and serial dilatation technique in percutaneous nephrolithotomy

BACKGROUND

Percutaneous nephrolithotomy (PCNL) is the first line treatment for treating kidney stones larger than 2 cm size with the advantages of lower morbidity and faster post-operative recovery. Creation of a nephrostomy access is one of the major steps of PCNL. It can be done either by single-step dilatation or by multi-step serial dilatation technique.

OBJECTIVES

To compare the outcome and evaluate the efficacy of percutaneous nephrolithotomy done by single-step versus serial dilatation technique with specific reference to access time, fluoroscopy time, rate of blood transfusion, length of hospital stay (post-op) and complication rate.

METHODS

It was a prospective study with a sample size of 100 where 50 patients underwent one-step dilatation and other 50 patients underwent serial-dilatation technique. These patients were analysed on the basis of their demographic profile, renal access time, total fluoroscopy time for access, post-operative haematuria, duration of post-operative hospital stay and complications after operative procedure. Data was analysed and reported using statistical tools.

RESULTS

Demographic profile of the patients and stone characteristics were equivalent between two groups. Mean access tract dilatation time, mean total fluoroscopy time were significantly less in one of the groups. Requirement of blood transfusion, and post-operative complications rate were not significant between two groups.

CONCLUSION

Both methods are safe and effective for tract dilatation. However, PCNL can be successfully performed by one-step dilatation with the added advantages of lesser time of renal access, lesser radiation exposure. Blood loss and hospital stay after operative procedure were not statistically significant between two groups.

One-stage tubeless percutaneous nephrolithotomy for asymptomatic calculous pyonephrosis

Background

In recent years, the safety and effectiveness of one-stage percutaneous nephrolithotomy (PCNL) for the treatment of calculous pyonephrosis have been proven. In order to further reduce postoperative pain and hospital stay, we first proposed and practiced the idea of one-stage tubeless percutaneous nephrolithotomy for calculous pyonephrosis.

Methods

A retrospective analysis was performed of case data of 30 patients with asymptomatic calculous pyonephrosis treated in our center with one-stage PCNL from January 2016 to January 2021. Patients were routinely given 20 mg of furosemide and 10 mg of dexamethasone sodium phosphate injection intravenously at the beginning of anesthesia. Among them, 27 patients successfully underwent one-stage tubeless percutaneous nephrolithotomy, while 3 cases were given indwelling nephrostomy tubes because of proposed second-stage surgery or the number of channels was greater than or equal to 3. All patients were operated on by the same surgeon.

Results

Preoperatively, 11 of 30 patients (8 men and 22 women) had positive urine bacterial cultures, and all were given appropriate antibiotics based on drug sensitivity tests. All patients completed the surgery successfully. The mean operative time was 66.6 ± 34.7 min, the mean estimated blood loss was 16.67 ± 14.34 mL and the mean postoperative hospital stay was 5.0 ± 3.1 days. The mean postoperative hospital stay was 4.6 ± 2.5 days among the 27 patients with one-stage tubeless percutaneous nephrolithotomy. Of the 3 patients with postoperative fever, 2 had the tubeless technique applied. One patient with 3 channels was given renal artery interventional embolization for control of postoperative bleeding. None of the 30 patients included in the study developed sepsis. The final stone-free rate was 93.3% (28/30) on repeat computed tomography at 1 month postoperatively. The final stone-free rate was 92.6% in the 27 patients undergoing one-stage tubeless percutaneous nephrolithotomy (25/27).

Conclusions

One-stage tubeless PCNL is an available and safe option in carefully evaluated and selected calculous pyonephrosis patients.

Anterograde Mini-Percutaneous Retropelvic Extra-Luminal Endopyelotomy: A Novel Approach to Uretero-Pelvic Junction Obstruction

Background Uretero-pelvic junction obstruction (UPJO) is a common cause of upper tract urinary obstruction. This condition is generally treated with various surgical options which include endoscopic (retrograde or anterograde), laparoscopic, open or robotic-assisted approaches. Herein, we describe a novel endoscopic retropelvic extra-luminal approach using a mini (14 Fr) nephroscope. Methods A 30-year-old male presented with symptomatic left UPJO and inferior pole renal stones, which were identified on computed tomography (CT) imaging. Mercaptuacetyltriglycine (MAG3) renogram demonstrated a functioning left kidney. With the patient positioned supine, a mini-perc (Karl-Storz) nephroscope was used to access the renal pelvis via the percutaneous route. The retropelvic space was thereafter accessed. Using a Holmium-YAG laser, the UPJO was splayed using an extra-luminal approach. Results Clear endoscopic vision, minimal bleeding, and overall satisfactory identification of the UPJO were achieved. At the 12-month follow-up, the patient remained stent and symptom-free. On follow-up CT imaging and MAG3 renogram, the system remained dilated with no obstruction noted. Conclusion Percutaneous anterograde retropelvic extra-luminal endopyelotomy is a novel approach that should be considered in patients with secondary renal calculi. This is the first report of the procedure being successfully performed utilizing the mini-perc access route.

Comparison of single-step renal dilatation and serial renal dilatation in percutaneous nephrolithotomy: A retrospective case-control study

Background:

Access to the pelvi-calyceal system and subsequent dilatation of the tract are among the initial important steps in percutaneous nephrolithotomy (PCNL). In this study, we share our experience with single-step renal dilatation when compared to multiple serial renal dilatation in PCNL.

Materials and Methods:

This is a retrospective study wherein 35 patients who underwent PCNL by single-step renal dilatation by appropriate size Amplatz Dilator were compared with 35 patients who underwent multi-step serial renal dilatation using serial metallic Alken dilators. These patients were analyzed on the basis of demographic profile, total intra-operative time, fluoroscopic time, intra-operative and postoperative complications, stone clearance, requirement of blood transfusion, duration of hospital stay, and follow-up.

Results:

There were no significant differences in the demographic profile among the patients in these two groups. The mean total operative duration and fluoroscopic duration were less in single step renal dilatation group, and these have been found to be statistically significant (P < 0.05). There were no statistically significant differences in the rates of other complications – incomplete stone clearance, bleeding and hematoma formation, requirement of blood transfusion, duration of hospital stay, and follow-up.

Conclusion:

Operative duration and rate of radiation exposure are significantly less in PCNL by single-step renal dilatation; however, there is no statistically significant difference in the rates of other complications.

Efficacy and safety of modified tract dilation technique using simultaneous pulling of proximal and distal ends of a guidewire for percutaneous nephrolithotomy in modified supine position

Purpose

Recently, the needs for supine percutaneous nephrolithotomy (PCNL) have become more increased because of an easy approach for endoscopic combined intrarenal surgery. However, making a nephrostomy tract during supine PCNL is more difficult than prone position due to movable kidney. To overcome this limitation, we used a modified nephrostomy tract dilation (MTD) technique using guidewire traction.

Materials and Methods

From January 2014 to June 2019, a total of 259 patients underwent PCNL in the modified supine position. Among them, the MTD technique was performed in 171 patients. For the MTD technique, two hydrophilic guidewires were passed from the nephrostomy tract and brought out through the urethra, then both proximal and distal ends were contralaterally pulled with tension for the easy placement of a fascia-cutting needle and a balloon catheter. We analyzed the efficacy of this technique in comparison with the conventional method.

Results

Intraoperative radiation exposure time (RET) (68.87 vs. 212.11 s) and hospital stay (5.90 vs. 6.74 days) were significantly shorter, while the success rate (77.2% vs. 63.6%) was significantly higher in the MTD group. Multivariate analysis showed that only the maximal stone diameter (odds ratio [OR], 1.928; 95% confidence interval [CI], 1.314–2.828; p=0.001) and MTD technique (OR, 0.017; 95% CI, 0.007–0.040; p<0.001) were independent factors for predicting short RET (<120 s).

Conclusions

This study demonstrated that MTD technique can be effectively and safely performed in modified supine position PCNL, and it can be helpful in reducing RET and enhancing success rates.